Fish Passage Site 10103550

Coordinates (dec. deg.): 55.91636°, -132.99113°
Legal Description: C069S081E04
Region: Southeast
Road Name: Coffman Cove Road

Datum: NAD83
Quad Name / ITM: Craig D-3
AWC Stream #:
Stream Name: Unnamed

Elevation:

Site Comments: Site between milepost 14 and 15.

Survey Date: Jun 01, 2017

Survey SEA17-CVR01

Observers: Mark Eisenman, Elizabeth Flory, Kelly Petty

Overall Fish Passage Rating: Gray

Tidal: No
Backwatered: No

Step Pools: No
Construction Year:


Comments: Open bottom arch, more of a bridge. Upstream and downstream gradient levels out after 100ft. Dolly Varden char captured upstream and downstream of crossing.

Culvert Measurements

ID: 1 Structure Type: Open-bottom arch (Structural steel plate) Fish Passage Rating: Gray
 
Length(ft): 48.2
Inlet Type: Headwall
Outlet Type: Headwall
Corrugation Depth(in.): 2.0
Corrugation Width(in.): 6.0
Condition Rating(1-5): 4
Approach Angle: 14.0
Sedimentation At Inlet:
Inlet Substrate: Cobble
Outlet Substrate: Bedrock
InletOutlet
Width(ft):13.8 12.4
Height(ft):8.0 15.8
Apron Length(ft):
Water Depth(ft): 0.12
Rustline Height(ft):0.0
Substrate Depth(ft):
Backwatered?: No
Baffles Present: No
Embedded?: Yes
Outfall Height: 0.0
Outfall Type: At Stream Grade
Constriction Ratio: 2.94
Culvert Gradient: 0.08%
Max Slope:
Max Slope Length:
 

Comments: Outlet at bedrock control grade, bedrock chute. Open bottom crossing, culvert is basically a bridge on concrete abuttments. Some deterioration of concrete noticed through out crossing. Concrete chutes inside crossing. Effective gradient through crossing is over 18% gradient .

Stream Measurements

Stream SubstratesUpstreamDownstream
Dominant:CobbleBedrock
Subdominant:GravelBoulder
Stream Slope(deg.):21.86
Stream Flow Stage:Medium
Stream Width Type Distance From
Crossing (ft)		 Stream
Width (ft)
Upstream ordinary high water 40.0 4.10
Upstream ordinary high water 200.0 5.20
Upstream ordinary high water 300.0 4.80

Elevations

Locator ID Culvert
Number		 River
Distance (ft)1		 Distance From
Crossing (ft)2		 Relative
Elevation (ft)
Road Elev 116.46
D/S Grade Ctrl (Thalweg) (End of downstream steep gradient) 0.00 80.46
D/S Water Surface Elev 0.00 80.51
D/S Water Surface Elev 37.00 88.60
D/S Grade Ctrl (Thalweg) (pool at outlet to bedrock chute) 37.00 88.71
Outlet Invert 68.00 96.49
D/S Water Surface Elev 68.00 96.61
Outlet Culvert Top (Invert embedded, elevation only relative to ITOP used for gradient) 68.00 107.19
Inlet Culvert Top (Invert embedded, elevation taken inverted only relative to OTOP) 116.20 107.24
Inlet Culvert Invert (1st resting) 116.20 105.18
U/S Water Surface Elev 116.20 105.34
U/S Grade Ctrl (Thalweg) 133.00 106.73
U/S Water Surface Elev 133.00 106.96

Notes:

  1. River distance is measured continuously throughout the survey reach along the thalweg of the stream.
  2. Measured from each end of the crossing along the thalweg of the stream.

Fish Sampling Efforts

Gear Type: Minnow Trap (A) Trap Duration(h): 2.3
Comments: 50ft upstream, dolly captured
 
Gear Type: Minnow Trap (B) Trap Duration(h): 2.3
Comments: set inside pipe, dolly captured

Fish Observations

Species: juvenile Dolly Varden Life History:
Total Fish Observed: 3 Fish Measured: 3 Fork Lengths (mm) Min: 66 Max: 93 Mean: 79
Collected/Observed by Gear Type: Downstream Minnow Trap (1)  Upstream Minnow Trap (2)  

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